Previously collected data for a multidisciplinary collaborative project organized by the National Institute of Mental Health are analyzed. The major objective of the collaborative research has been the testing of a wide range of hypotheses which implicate neurochemistry in the etiology and maintenance of affective disorders. Several behavioral and biological systems were assessed before and after treatment, so that the relationship of pretreatment variables to outcome or change in biological variables as a function of treatment could be obtained. Hypotheses are of several types. Some address single biological systems while others address interactive hypotheses between biological systems (for example, interactions between adrenergic, serotonergic, enzyme, neuroendocrine, and electrolyte systems). Subjects include approximately 94 manic disorder patients, and 66 control subjects. The collaborators in this research program are Yale University (U01MH026976), the University of Pennsylvania (U01MH026977), Washington University (U01MH026978), Cornell University Medical College (U01MH026979) and Illinois State Psychiatric Institute (U01MH026975).